x86: acpi: Name fields in FADT in accordance with specification

ACPI specification defines FADT fields marked as reserved in U-Boot.

Name these fields in accordance with ACPI specification.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/include/asm/acpi_table.h

@@ -178,9 +178,8 @@ struct __packed acpi_fadt {
 	u32 flags;
 	struct acpi_gen_regaddr reset_reg;
 	u8 reset_value;
-	u8 res3;
-	u8 res4;
-	u8 res5;
+	u16 arm_boot_arch;
+	u8 minor_revision;
 	u32 x_firmware_ctl_l;
 	u32 x_firmware_ctl_h;
 	u32 x_dsdt_l;